Inverter fault detection method, device and electronic equipment

Abstract

The application discloses an inverter fault detection method and device and electronic equipment. It is related to the field of inverters. The method comprises the following steps: determining the cycle length of the collection cycle for collecting the three-phase current signals output by the inverter, and dividing the time range corresponding to the cycle length into a plurality of first target time ranges; collecting the three-phase current signals output by the inverter in the first target collection cycle to obtain a three-phase current signal group corresponding to each first target time range; determining the first change rate corresponding to each three-phase current signal group based on the three-phase current signals contained in each three-phase current signal group; and determining whether the inverter has a fault based on the first change rate corresponding to each three-phase current signal group. The application solves the technical problem of low detection efficiency caused by the complex fault detection link of the inverter in the prior art.

Description

Technical Field

[0001] This invention relates to the field of inverters, and more specifically, to an inverter fault detection method, apparatus, and electronic device. Background Technology

[0002] Three-phase inverters often experience faults during actual operation due to overvoltage, overcurrent, and device over-temperature aging, with most of these faults being insulated-gate bipolar transistor (IGBT) failures. Common IGBT faults include short-circuit faults and open-circuit faults. When a short-circuit fault occurs in the system due to electrical breakdown or thermal breakdown, the system's hardware circuitry will detect and handle it promptly. The common practice is to directly disconnect the fault or connect a fast-acting fuse in series in the circuit to convert the short-circuit fault into an open-circuit fault. Therefore, research on IGBT fault diagnosis mainly focuses on IGBT open-circuit faults. After an IGBT open-circuit fault occurs, the inverter and load can still operate for a short period, but the output current will be severely distorted. If this is not detected and handled promptly, it will cause secondary damage to the inverter and load. Therefore, research on open-circuit fault diagnosis of inverter IGBTs is of great significance.

[0003] Currently, the fault detection process for inverters in related technologies (such as detecting faults by measuring the power corresponding to the positive and negative half-waves of the current in each phase) is complex, resulting in low detection efficiency. No effective solution has yet been proposed to address these issues. Summary of the Invention

[0004] This invention provides an inverter fault detection method, apparatus, and electronic device to at least solve the technical problem of low detection efficiency caused by the complexity of the fault detection process in the prior art.

[0005] According to one aspect of the present invention, an inverter fault detection method is provided, comprising: determining the period length of a collection period for collecting three-phase current signals output by the inverter, and dividing the time range corresponding to the period length into multiple first target time ranges; collecting the three-phase current signals output by the inverter within the first target collection period to obtain a three-phase current signal group corresponding to each first target time range, wherein each three-phase current signal group consists of two three-phase current signals, and the collection times of the two three-phase current signals are the initial time and the end time of the first target time range, respectively; determining a first rate of change corresponding to each three-phase current signal group based on the three-phase current signals contained in each three-phase current signal group, wherein the first rate of change characterizes the rate of change of the current vector angle of the current three-phase current signal group within the first target time range; and determining whether the inverter has malfunctioned based on the first rate of change corresponding to each three-phase current signal group.

[0006] Furthermore, the inverter fault detection method also includes: transforming the first three-phase current signal from a three-phase stationary coordinate system to a two-phase stationary coordinate system to obtain a first current value of the first three-phase current signal on the α-axis and a second current value of the first three-phase current signal on the β-axis, wherein the first three-phase current signal and the second three-phase current signal are used to form a target three-phase current signal group, which is any one of multiple three-phase current signal groups; transforming the second three-phase current signal from a three-phase stationary coordinate system to a two-phase stationary coordinate system to obtain a third current value of the second three-phase current signal on the α-axis and a fourth current value of the second three-phase current signal on the β-axis; and determining a first rate of change corresponding to the target three-phase current signal group based on the first current value, the second current value, the third current value, the fourth current value, and a first target time range corresponding to the target three-phase current signal group.

[0007] Furthermore, the inverter fault detection method also includes: calculating the deviation between each first rate of change and the target rate of change to obtain multiple target deviation values, wherein the target rate of change is the rate of change of the current vector angle corresponding to the three-phase current signal when the inverter has not experienced a fault; determining the average deviation value within the first target acquisition period based on each target deviation value and the first target time range corresponding to the target deviation value; and determining whether the inverter has experienced a fault based on the average deviation value and the target rate of change.

[0008] Furthermore, the inverter fault detection method also includes: calculating the ratio of the average deviation value to the target rate of change to obtain the calculation result; if the calculation result is greater than or equal to a first preset threshold, it is determined that the inverter has failed; if the calculation result is less than the first preset threshold, it is determined that the inverter has not failed.

[0009] Furthermore, the inverter fault detection method also includes: after determining whether the inverter has failed, if the inverter has failed, determining the target three-phase current signal corresponding to the inverter within the second target acquisition period, wherein the first target acquisition period and the second target acquisition period have the same period length; decomposing each phase current signal in the target three-phase current signal to obtain multiple current values ​​corresponding to each phase current signal within the second target time range, and multiple current values ​​corresponding to each phase current signal within the third target time range, wherein the time range corresponding to the second target acquisition period consists of the second target time range and the third target time range; normalizing the current value corresponding to each phase current signal at the target time based on the target reference value corresponding to the target time, to obtain the first target per-unit set corresponding to each phase current signal within the first target time range, and the second target per-unit set corresponding to each phase current signal within the second target time range, wherein the target time is any time within the second target acquisition period, and the target reference value is a variable related to the time factor; and determining the faulty insulated gate bipolar transistor (IGBT) from the insulated gate bipolar transistors (IGBTs) in the inverter based on the first target per-unit set and the second target per-unit set.

[0010] Furthermore, the inverter fault detection method also includes: before normalizing the current value of each phase current signal at the target time based on the target reference value at the target time, transforming the target three-phase current signal from the three-phase stationary coordinate system to the two-phase rotating coordinate system to obtain the current value information of the target three-phase current signal on the d-axis and the current value information of the target three-phase current signal on the q-axis; and determining the target reference value based on the current value information of the target three-phase current signal on the d-axis and the current value information of the target three-phase current signal on the q-axis.

[0011] Furthermore, the inverter fault detection method also includes: calculating the mean of the first target per-unit quantities contained in each first target per-unit quantity set to obtain a first target mean corresponding to each first target per-unit quantity set; calculating the mean of the second target per-unit quantities contained in each second target per-unit quantity set to obtain a second target mean corresponding to each second target per-unit quantity set; comparing each first target mean with a second preset threshold to obtain a first comparison result, and comparing each second target mean with a second preset threshold to obtain a second comparison result; and determining the faulty insulated gate bipolar transistor in the inverter based on the first comparison result and the second comparison result.

[0012] According to another aspect of the present invention, an inverter fault detection device is also provided, comprising: a first determining module, configured to determine the period length of the acquisition period for acquiring the three-phase current signal output by the inverter, and divide the time range corresponding to the period length into multiple first target time ranges; an acquisition module, configured to acquire the three-phase current signal output by the inverter within the first target acquisition period, and obtain a three-phase current signal group corresponding to each first target time range, wherein each three-phase current signal group consists of two three-phase current signals, and the acquisition times of the two three-phase current signals are the initial time and the end time of the first target time range, respectively; a second determining module, configured to determine a first rate of change corresponding to each three-phase current signal group based on the three-phase current signals contained in each three-phase current signal group, wherein the first rate of change characterizes the rate of change of the current vector angle of the current three-phase current signal group within the first target time range; and a third determining module, configured to determine whether the inverter has malfunctioned based on the first rate of change corresponding to each three-phase current signal group.

[0013] According to another aspect of the present invention, a computer-readable storage medium is also provided, wherein a computer program is stored in the computer-readable storage medium, and the computer program is configured to execute the above-described inverter fault detection method when running.

[0014] According to another aspect of the present invention, an electronic device is also provided, the electronic device including one or more processors; a memory for storing one or more programs, wherein when the one or more programs are executed by the one or more processors, the one or more processors are configured to run the programs, wherein the programs are configured to execute the inverter fault detection method described above during runtime.

[0015] In this embodiment of the invention, a method is adopted to determine whether the inverter has failed by determining the rate of change of the current vector angle based on the three-phase current signals of the inverter at different times. This is achieved by determining the period length of the acquisition cycle for collecting the three-phase current signals output by the inverter, dividing the time range corresponding to the period length into multiple first target time ranges, and then acquiring the three-phase current signals output by the inverter within the first target acquisition cycle to obtain a three-phase current signal group corresponding to each first target time range. Next, based on the three-phase current signals contained in each three-phase current signal group, a first rate of change corresponding to each three-phase current signal group is determined, thereby determining whether the inverter has failed based on the first rate of change corresponding to each three-phase current signal group. Each three-phase current signal group consists of two three-phase current signals, and the acquisition times of the two three-phase current signals are the initial and end times of the first target time range, respectively. The first rate of change characterizes the rate of change of the current vector angle of the current three-phase current signal group within the first target time range.

[0016] In the above process, by determining the rate of change of the current vector angle of the inverter in multiple time periods within the first target acquisition cycle based on the three-phase current signals of the inverter at different times, and then determining whether the inverter has failed based on the rate of change of the current vector angle, this avoids the need for detecting inverter faults by detecting the power corresponding to the positive and negative half-waves of each phase current, as is done in related technologies. This simplifies the detection process in inverter fault diagnosis and effectively improves fault detection efficiency. Furthermore, since the rate of change of the current vector angle of the three-phase current differs depending on whether the inverter has failed or not, determining whether the inverter has failed based on the rate of change of the current vector angle enables accurate fault detection.

[0017] Therefore, the solution provided in this application achieves the goal of determining the rate of change of the current vector angle based on the three-phase current signal of the inverter at different times, thereby determining whether the inverter has failed. This achieves the technical effect of improving fault detection efficiency and solves the technical problem of low detection efficiency caused by the complexity of the fault detection process of the inverter in the prior art. Attached Figure Description

[0018] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this application, illustrate exemplary embodiments of the invention and, together with their description, serve to explain the invention and do not constitute an undue limitation thereof. In the drawings:

[0019] Figure 1 This is a schematic diagram of an optional inverter fault detection method according to an embodiment of the present invention;

[0020] Figure 2 This is a schematic diagram of the current vector angle of an optional three-phase current according to an embodiment of the present invention;

[0021] Figure 3 This is a schematic diagram of an optional single-tube open-circuit fault current vector path according to an embodiment of the present invention;

[0022] Figure 4 This is a schematic diagram of an optional inverter fault detection method according to an embodiment of the present invention;

[0023] Figure 5 This is a schematic diagram illustrating an optional first rate of change according to an embodiment of the present invention;

[0024] Figure 6 This is an exploded schematic diagram of an optional single-phase current according to an embodiment of the present invention;

[0025] Figure 7 This is a schematic diagram of an optional single-phase current taking the absolute value according to an embodiment of the present invention;

[0026] Figure 8 This is a schematic diagram of an optional inverter fault detection device according to an embodiment of the present invention;

[0027] Figure 9 This is a schematic diagram of an optional electronic device according to an embodiment of the present invention. Detailed Implementation

[0028] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0029] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0030] Example 1

[0031] According to an embodiment of the present invention, an embodiment of an inverter fault detection method is provided. It should be noted that the steps shown in the flowchart in the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions. Furthermore, although a logical order is shown in the flowchart, in some cases, the steps shown or described may be executed in a different order than that shown here.

[0032] Figure 1 This is a schematic diagram of an optional inverter fault detection method according to an embodiment of the present invention, such as... Figure 1 As shown, the method includes the following steps:

[0033] Step S101: Determine the period length of the acquisition period for acquiring the three-phase current signal output by the inverter, and divide the time range corresponding to the period length into multiple first target time ranges.

[0034] Optionally, we will first explain the three-phase output current of the inverter. The output current of each phase of the inverter is a sine wave, with the positive half-wave generated by the upper bridge arm and the negative half-wave generated by the lower bridge arm. When an open-circuit fault occurs in a bridge arm, the corresponding current portion of the bridge arm will be missing. Therefore, fault diagnosis can be performed by analyzing the characteristics of the three-phase current fault waveform.

[0035] In step S101, the period length of the acquisition cycle for collecting the three-phase current signal output by the inverter can be determined by electronic devices, application systems, servers, etc. In this application, the period length of the acquisition cycle for collecting the three-phase current signal output by the inverter is determined by a fault detection system, so as to determine whether the inverter has failed in each acquisition cycle based on the acquisition results of each acquisition cycle. Optionally, the period length of the acquisition cycle can be the period length of the sine wave corresponding to the three-phase current output by the inverter, or it can be a multiple of the period length of the sine wave corresponding to the three-phase current output by the inverter.

[0036] Furthermore, once the acquisition cycle length is determined, the fault detection system can divide the time range corresponding to the cycle length into multiple first target time ranges. The time lengths corresponding to each first target time range can be the same or different. Specifically, the first target time range can be used to characterize the first 0-0.1s, the first 0.1-0.2s, etc., within the time range corresponding to the cycle length.

[0037] Step S102: Within the first target acquisition period, the three-phase current signal output by the inverter is acquired to obtain a three-phase current signal group corresponding to each first target time range. Each three-phase current signal group consists of two three-phase current signals, and the acquisition times of the two three-phase current signals are the initial time and the end time of the first target time range, respectively.

[0038] In step S102, the first target acquisition period can be any acquisition period or an acquisition period corresponding to a fixed time period. The fault detection system can acquire the three-phase current signals output by the inverter within the first target acquisition period to obtain a group of three-phase current signals corresponding to each first target time range. For example, when a certain first target time range is the first 0.1-0.2 seconds of the time range corresponding to the period length, the two three-phase current signals in the group of three-phase current signals corresponding to that first target time range are acquired at 0.1 seconds and 0.2 seconds after the initial moment of the time range corresponding to the first target acquisition period, respectively. It should also be noted that adjacent groups of three-phase current signals corresponding to first target time ranges may contain the same three-phase current signals. For example, when a certain first target time range is the first 0.2-0.3 seconds of the time range corresponding to the period length, the two three-phase current signals in the group of three-phase current signals corresponding to that first target time range are acquired at 0.2 seconds and 0.3 seconds after the initial moment of the time range corresponding to the first target acquisition period, respectively.

[0039] It should be noted that by acquiring the three-phase current signals output by the inverter over multiple time periods, it is easier to determine the rate of change of the current vector angle corresponding to each time period. This can effectively avoid the failure to detect faults when the acquisition time interval is too long and the fault period occurs between the acquisition time intervals.

[0040] Step S103: Based on the three-phase current signals contained in each three-phase current signal group, determine the first rate of change corresponding to each three-phase current signal group, wherein the first rate of change characterizes the rate of change of the current vector angle of the current three-phase current signal group within the first target time range.

[0041] Optionally, when the inverter is operating normally, the three-phase current output by the inverter is a balanced three-phase sine wave. If a 3s / 2s transformation is performed on the three-phase current pairs, then as follows: Figure 2 The diagram shows the current vector angles of the three-phase currents, with current vector I. s Will surround Figure 2 The origin of the coordinate axes rotates at a constant speed and equal value, following a circular trajectory. The angle value θ of the current vector is... s It also increases at a constant rate within a cycle, with a rate of change that is non-zero and constant. When an open-circuit fault occurs in the inverter, such as... Figure 3 The diagram shows the current vector path during a single-tube open-circuit fault. The absence of current will cause the range of rotation of the current vector to no longer be a complete circle, and the angle value of the current vector will not continue to increase at a constant rate. During the missing time period, it will remain constant, and its rate of change will remain zero.

[0042] Therefore, in step S103, the fault detection system can determine the rate of change of the current vector angle corresponding to each three-phase current signal group (i.e., the aforementioned first rate of change) based on the three-phase current signals contained in each three-phase current signal group, that is, determine the rate of change of the current vector angle corresponding to each first target time range within the first target acquisition period of the inverter.

[0043] It should be noted that by determining the rate of change of the current vector angle of the inverter in multiple time periods within the first target acquisition cycle based on the three-phase current signals of the inverter at different times, the detection process in inverter fault diagnosis is simplified, thereby effectively improving fault detection efficiency.

[0044] Step S104: Determine whether the inverter has malfunctioned based on the first rate of change corresponding to each three-phase current signal group.

[0045] In step S104, the fault detection system can compare the first rate of change corresponding to each three-phase current signal group to determine whether the first rate of change corresponding to each three-phase current signal group is the same, thereby determining whether the inverter has failed based on the comparison result. For example, when at least one first rate of change is different from all other first rates of change, and the difference is greater than or equal to a preset threshold, the inverter is determined to have failed. When the fluctuation range of each first rate of change is within a preset range, the inverter is determined not to have failed. Optionally, the fault detection system can also compare the first rate of change corresponding to each three-phase current signal group with a target rate of change, where the target rate of change is the rate of change of the current vector angle corresponding to the three-phase current signal when the inverter has not failed. Based on this comparison result, the system determines whether the inverter has failed. For example, when at least one first rate of change is different from the target rate of change, and the difference is greater than or equal to a preset threshold, the inverter is determined to have failed. When the fluctuation range of each first rate of change relative to the target rate of change is within a preset range, the inverter is determined not to have failed. Optionally, the fault detection system can also determine whether the inverter has failed based on the first rate of change corresponding to each three-phase current signal group, using other methods.

[0046] Based on the scheme defined in steps S101 to S104 above, it can be understood that in this embodiment of the invention, the method of determining whether the inverter has failed is based on the rate of change of the current vector angle according to the three-phase current signals of the inverter at different times. This is achieved by determining the period length of the acquisition period for collecting the three-phase current signals output by the inverter, dividing the time range corresponding to the period length into multiple first target time ranges, and then collecting the three-phase current signals output by the inverter within the first target acquisition period to obtain a three-phase current signal group corresponding to each first target time range. Next, based on the three-phase current signals contained in each three-phase current signal group, the first rate of change corresponding to each three-phase current signal group is determined, thereby determining whether the inverter has failed based on the first rate of change corresponding to each three-phase current signal group. Each three-phase current signal group consists of two three-phase current signals, and the acquisition times of the two three-phase current signals are the initial and end times of the first target time range, respectively. The first rate of change characterizes the rate of change of the current vector angle of the current three-phase current signal group within the first target time range.

[0047] It is noteworthy that in the above process, by determining the rate of change of the current vector angle of the inverter for multiple time periods within the first target acquisition cycle based on the three-phase current signals of the inverter at different times, and then determining whether the inverter has malfunctioned based on the rate of change of the current vector angle, this avoids the need for detecting inverter faults by detecting the power corresponding to the positive and negative half-waves of each phase current, as is done in related technologies. This simplifies the detection process in inverter fault diagnosis and effectively improves fault detection efficiency. Furthermore, since the rate of change of the current vector angle of the three-phase current differs when the inverter is faulty and when it is not faulty, determining whether the inverter has malfunctioned based on the rate of change of the current vector angle allows for accurate fault detection.

[0048] Therefore, the solution provided in this application achieves the goal of determining the rate of change of the current vector angle based on the three-phase current signal of the inverter at different times, thereby determining whether the inverter has failed. This achieves the technical effect of improving fault detection efficiency and solves the technical problem of low detection efficiency caused by the complexity of the fault detection process of the inverter in the prior art.

[0049] In one optional embodiment, during the process of determining the first rate of change corresponding to each three-phase current signal group based on the three-phase current signals contained in each three-phase current signal group, the fault detection system can transform the first three-phase current signal from a three-phase stationary coordinate system to a two-phase stationary coordinate system to obtain a first current value of the first three-phase current signal on the α-axis and a second current value of the first three-phase current signal on the β-axis. Similarly, it can transform the second three-phase current signal from a three-phase stationary coordinate system to a two-phase stationary coordinate system to obtain a third current value of the second three-phase current signal on the α-axis and a fourth current value of the second three-phase current signal on the β-axis. Therefore, based on the first, second, third, and fourth current values ​​and a first target time range corresponding to the target three-phase current signal group, the first rate of change corresponding to the target three-phase current signal group is determined. The first and second three-phase current signals are used to form the target three-phase current signal group, which is any one of multiple three-phase current signal groups.

[0050] Optionally, since it is difficult to determine whether an inverter has an open-circuit fault in practical fault diagnosis by the rotation range of the current vector, this application uses the change in the value of the first rate of change before and after an IGBT open-circuit fault occurs in the inverter to determine whether a fault has occurred. Specifically, the first rate of change can be determined based on the following formula:

[0051]

[0052] Among them, F i θ represents the first rate of change corresponding to the i-th three-phase current signal group. s This represents the angle of the current vector. Where dθ s It can be calculated using the following formula:

[0053]

[0054] in, This represents the angle of the current vector corresponding to the later-acquired three-phase current signal in the target three-phase current signal group. This represents the current vector angle corresponding to the first three-phase current signal acquired in the target three-phase current signal group. In this embodiment, the first three-phase current signal is taken as the subsequently acquired three-phase current signal, and the second three-phase current signal is taken as the first acquired three-phase current signal for explanation.

[0055] Furthermore, in, This represents the first current value of the first three-phase current signal on the α axis. i represents the second current value of the first three-phase current signal on the β axis. k This represents the current value of the first three-phase current signal, and

[0056] Therefore, the first rate of change corresponding to each three-phase current signal group can be calculated using the following formula:

[0057]

[0058] in, This represents the third current value of the second and third phase current signals on the α axis. This represents the fourth current value of the second and third phase current signals on the β axis, Δt. i This represents the time interval between the initial and final moments within the first target time range corresponding to the i-th target three-phase current signal group.

[0059] Therefore, for any three-phase current signal group, such as Figure 4 As shown, the fault detection system can perform a 3s / 2s transformation on both three-phase current signals contained in the three-phase current signal group, that is, transform the two three-phase current signals from a three-phase stationary coordinate system to a two-phase stationary coordinate system, thereby obtaining the current value of each three-phase current signal on the α-axis and the current value on the β-axis. Then, based on the current value of each three-phase current signal on the α-axis and the current value on the β-axis, and the first target time range corresponding to the three-phase current signal group, the first rate of change corresponding to the target three-phase current signal group can be determined.

[0060] It should be noted that by performing a 3s / 2s transformation on the three-phase current signals in the three-phase current signal group, and determining the first rate of change corresponding to the three-phase current signal group based on the transformation result, the accurate determination of the first rate of change is achieved.

[0061] In one optional embodiment, during the process of determining whether the inverter has failed based on the first rate of change corresponding to each three-phase current signal group, the fault detection system can calculate the deviation between each first rate of change and a target rate of change to obtain multiple target deviation values. Then, based on each target deviation value and the first target time range corresponding to that target deviation value, the average deviation value within the first target acquisition period is determined. Thus, based on the average deviation value and the target rate of change, it is determined whether the inverter has failed. The target rate of change is the rate of change of the current vector angle corresponding to the three-phase current signal when the inverter has not failed.

[0062] Optional, Figure 5 This is a schematic diagram illustrating the change in the first rate of change, as shown below. Figure 5 As shown in the diagram, the horizontal axis represents time, and the vertical axis represents the value of the first rate of change. When the inverter is fault-free, the value of the aforementioned first rate of change is not zero and is a constant value. Therefore, this value is set as F. ε(That is, the aforementioned target rate of change). When an open-circuit fault occurs in the inverter, the trajectory of the vector motion formed by the three-phase current signals on the α-axis and the β-axis is a straight line, meaning the three-phase current signals on the α-axis and β-axis are directly proportional. The corresponding first rate of change is zero. Therefore, if an open-circuit fault occurs within a certain sampling period, the first rate of change will change abruptly. For example, Figure 5 As shown, the percentage of the sudden change time in the cycle length T depends on the location of the fault and the number of faulty IGBTs. A single IGBT fault accounts for 50%, faults in the same bridge arm between upper and lower IGBTs account for 100%, faults in two IGBTs on opposite sides of different bridge arms account for 66.7%, and faults in two IGBTs on the same side of different bridge arms account for 83.3%. Therefore, when the inverter is fault-free, the value of k is approximately 0.

[0063] Specifically, after determining the first rate of change for each three-phase current signal group, the fault detection system can first determine multiple target deviation values ​​based on the following formula:

[0064] ε i =|F ε -F i |

[0065] Where, ε i F represents the target deviation corresponding to the i-th three-phase current signal group. ε This represents the rate of change of the target.

[0066] Then, the average deviation value within the first target acquisition period can be determined based on the following formula:

[0067]

[0068] in, The value represents the average deviation, and T represents the period length corresponding to the first target acquisition period.

[0069] Furthermore, such as Figure 4 As shown, after determining the average deviation value, the fault detection system can determine the ratio of the average deviation value to the target rate of change, and thus determine whether the inverter has failed based on whether the ratio is greater than a preset ratio. Optionally, the fault detection system can also determine the difference between the average deviation value and the target rate of change, and thus determine whether the inverter has failed based on whether the difference is greater than a preset difference.

[0070] It should be noted that by combining the target rate of change and determining whether the inverter has malfunctioned based on the deviation between the first rate of change and the target rate of change, the accuracy of fault detection can be effectively improved.

[0071] In one optional embodiment, during the process of determining whether the inverter has failed based on the average deviation value and the target rate of change, the fault detection system can calculate the ratio of the average deviation value to the target rate of change to obtain the calculation result. If the calculation result is greater than or equal to a first preset threshold, the inverter is determined to have failed; if the calculation result is less than the first preset threshold, the inverter is determined not to have failed.

[0072] Optionally, the fault detection system can divide the average deviation value by the target rate of change to obtain the calculation result. Then, the following diagnostic variables can be defined:

[0073]

[0074] Where S represents the diagnostic variable, k m This represents the first preset threshold. The fault detection system can determine that the inverter has failed when S=1, and determine that the inverter has not failed when S=0.

[0075] In one optional embodiment, when a single IGBT in the inverter fails, the value of k is approximately 1 / 2; when IGBTs on opposite sides of the same bridge arm fail, the value of k is approximately 1; when two IGBTs on opposite sides of different bridge arms fail, the value of k is approximately 2 / 3; and when two IGBTs on the same side of different bridge arms fail, the value of k is approximately 5 / 6. Therefore, by monitoring the value of k in real time during inverter operation, not only can an open-circuit fault be detected in the inverter in real time, but the type of fault can also be quickly determined. This not only enables more accurate fault detection but also effectively improves fault detection efficiency and reduces troubleshooting time.

[0076] In one optional embodiment, after determining whether the inverter has failed, if the inverter has failed, the fault detection system can determine the target three-phase current signal corresponding to the inverter within the second target acquisition period, and decompose the current signal of each phase in the target three-phase current signal to obtain multiple current values ​​corresponding to each phase current signal within the second target time range, and multiple current values ​​corresponding to each phase current signal within the third target time range. Based on the target reference value corresponding to the target time, the current value corresponding to each phase current signal at the target time is normalized to obtain a first target per-unit set corresponding to each phase current signal within the first target time range, and a second target per-unit set corresponding to each phase current signal within the second target time range. Based on the first and second target per-unit sets, the faulty insulated-gate bipolar transistor (IGBT) in the inverter is determined. The first target acquisition period and the second target acquisition period have the same period length. The time range corresponding to the second target acquisition period consists of the second target time range and the third target time range. The target time is any time within the second target acquisition period, and the target reference value is a variable associated with the time factor.

[0077] Optionally, once an open-circuit fault is detected in the inverter, fault location can be achieved using the per-unit average method. Specifically, such as... Figure 6 As shown, the current in each phase of the inverter can be considered as the superposition of two currents: the positive half-wave and the negative half-wave. If these two currents are decomposed separately, the state of each bridge arm can be reflected. Therefore, as... Figure 4 , Figure 6 As shown, the fault detection system can determine the target three-phase current signal (e.g., ...) corresponding to the inverter during the second target acquisition cycle. Figure 6 (As shown on the left in the image), and decompose the current signal of each phase in the target three-phase current signal to obtain the following: Figure 6 The right side of the image shows the current variables (i.e., the aforementioned multiple current values) corresponding to the positive half-wave portion (corresponding to the second target time range) of each phase current signal, and the current variables corresponding to the negative half-wave portion (corresponding to the second target time range) of each phase current signal. Figure 6 The horizontal axis represents time, and the vertical axis represents current value. Each current value in the current variable is associated with a time within the second target acquisition cycle. The aforementioned second target acquisition cycle can be the first target acquisition cycle or any acquisition cycle after the first target acquisition cycle.

[0078] After that, as Figure 7 As shown, the fault detection system can detect the corresponding current variables (such as the negative half-wave portion of the three-phase current) in each phase. Figure 7 (As shown on the left) Take the absolute value to obtain as shown below. Figure 7The current variables shown on the right side ultimately yield six sets of positive current variables corresponding to the three-phase currents, among which... Figure 7 The horizontal axis represents time, and the vertical axis represents current values. Each group of current variables consists of multiple current values ​​corresponding to either the positive half-wave or the negative half-wave. These six groups of current variables are respectively the current variables i corresponding to the positive half-wave of phase A current. A+ The current variable i corresponding to the negative half-wave portion of the A-phase current A- The current variable i corresponding to the positive half-wave portion of the B-phase current B+ The current variable i corresponding to the negative half-wave portion of the B-phase current. B- The current variable i corresponding to the positive half-wave portion of the C-phase current C+ The current variable i corresponding to the negative half-wave portion of the C-phase current C- .

[0079] Furthermore, such as Figure 4 As shown, the fault detection system can normalize the current value of each current variable at a certain time (i.e., the target time) based on the target reference value. This results in a first set of target per-unit quantities corresponding to the current variables in the positive half-wave portion of each phase current signal, and a second set of target per-unit quantities corresponding to the current variables in the negative half-wave portion of each phase current signal. In simpler terms, since both the current variables and the target reference value are time-dependent variables—that is, variables that may change over time—the target reference value at the corresponding time is used for processing current values ​​at the same moment during the normalization process.

[0080] Furthermore, after obtaining three first target per-unit sets and three second target per-unit sets, the fault detection system can identify the faulty insulated-gate bipolar transistor (IGBT) from the insulated-gate bipolar transistors in the inverter based on the first and second target per-unit sets.

[0081] It should be noted that by locating the fault only after it has been detected through fault identification, the burden on the relevant system during normal, fault-free periods can be reduced. On the other hand, by decomposing the current signal of each phase in the target three-phase current signal, the resulting decomposed current can reflect the state of each bridge arm, thereby facilitating accurate fault location.

[0082] In one optional embodiment, before normalizing the current value of each phase current signal at the target time based on the target reference value at the target time, the fault detection system can transform the target three-phase current signal from a three-phase stationary coordinate system to a two-phase rotating coordinate system to obtain the current value information of the target three-phase current signal on the d-axis and the current value information of the target three-phase current signal on the q-axis, thereby determining the target reference value based on the current value information of the target three-phase current signal on the d-axis and the current value information of the target three-phase current signal on the q-axis.

[0083] Optional, such as Figure 4 As shown, the fault detection system performs a 3s / 2r transformation on the target three-phase current signal during the second acquisition cycle, that is, transforms the target three-phase current signal from a three-phase stationary coordinate system to a two-phase rotating coordinate system, thereby obtaining the current value information of the target three-phase current signal on the d-axis and the current value information on the q-axis. The current value information of the target three-phase current signal on the d-axis represents the component of the target three-phase current signal on the d-axis at each moment during the second acquisition cycle, and the current value information of the target three-phase current signal on the q-axis represents the component of the target three-phase current signal on the q-axis at each moment during the second acquisition cycle.

[0084] Furthermore, such as Figure 4 As shown, once the current values ​​of the target three-phase current signals on the d-axis and q-axis are determined, the fault detection system can determine the target reference value at a certain moment based on the following formula:

[0085]

[0086] Among them, i e i represents the target baseline value at a certain moment. d This represents the d-axis component of the target three-phase current signal at that moment, i q The q-axis component of the target three-phase current signal at this moment.

[0087] Therefore, the target reference value for each moment in the second acquisition cycle can be determined based on the aforementioned method.

[0088] In one optional embodiment, during the process of determining the faulty insulated-gate bipolar transistor (IGBT) from the insulated-gate bipolar transistors (IGBTs) in the inverter based on a first target per-unit set and a second target per-unit set, the fault detection system can calculate the average of the first target per-unit values ​​contained in each first target per-unit set to obtain a first target average value corresponding to each first target per-unit set. Then, it can calculate the average of the second target per-unit values ​​contained in each second target per-unit set to obtain a second target average value corresponding to each second target per-unit set. By comparing each first target average value with a second preset threshold, a first comparison result is obtained. Then, each second target average value is compared with the second preset threshold to obtain a second comparison result. Finally, based on the first comparison result and the second comparison result, the faulty IGBT in the inverter is determined.

[0089] Optional, such as Figure 4 As shown, the fault detection system can calculate the average value of each set of first target per-unit quantities to obtain the first target mean value corresponding to the positive half-wave portion of the A-phase current. The first target mean value corresponding to the positive half-wave portion of the B-phase current The first target mean value corresponding to the positive half-wave portion of the C-phase current The second target mean corresponding to the negative half-wave portion of the A-phase current The second target mean corresponding to the negative half-wave portion of the B-phase current The second target mean corresponding to the negative half-wave portion of the C-phase current

[0090] Furthermore, the first target mean It can be used to determine whether the IGBT in the upper arm of the first group of bridge arms is faulty, with the first target average value. It can be used to determine whether the IGBT in the upper arm of the second bridge arm is faulty, with the first target mean value. It can be used to determine whether the IGBT in the upper arm of the third bridge arm is faulty, and secondly, to set the target average. It can be used to determine whether the IGBT in the lower arm of the first group of bridge arms is faulty, and the second target is the average value. It can be used to determine whether the IGBT in the lower arm of the second bridge arm is faulty, and the second target mean. It can be used to determine whether the IGBT in the lower arm of the third bridge arm is faulty.

[0091] In one optional embodiment, when the inverter is fault-free, the three-phase current on the AC side is complete, and the three first target averages and three second target averages are all greater than or equal to the second preset threshold. When a single IGBT fails, a half-wave of a certain phase of the three-phase current on the AC side will be missing, and its corresponding target average will be less than the second preset threshold. The remaining target averages will change compared to normal conditions, but will still be greater than or equal to the second preset threshold. There are three scenarios for dual IGBT failures: If the fault location is on two IGBTs on the same bridge arm, the current in the corresponding phases of the upper and lower bridge arms will be completely missing, and the two corresponding target averages will be less than the second preset threshold, while the rest will be greater than or equal to the second preset threshold; if the fault location is on two IGBTs on opposite sides of different bridge arms, the target average corresponding to the faulty bridge arm will be less than the second preset threshold, while the remaining target averages will be greater than or equal to the second preset threshold; if the fault location is on two IGBTs on the same side of different bridge arms, in addition to the current in the faulty bridge arm being missing, the current on the opposite side of the non-faulty phase will also be missing. Therefore, in this case, three target averages will be less than the second preset threshold, while the remaining target averages will be greater than or equal to the second preset threshold.

[0092] Optional, such as Figure 4 As shown, when the fault detection system detects that the aforementioned diagnostic variable S changes from 0 to 1, it will begin fault localization. The following localization variables can be defined:

[0093]

[0094] Where X represents the location variable, i m This indicates the second preset threshold. This represents the target mean, where the target mean is... or or or or or

[0095] Furthermore, when an IGBT in one of the bridge arms fails, the corresponding target average value will be lower than the second preset threshold, and the location variable will change from 0 to 1. Thus, the fault location of the inverter can be accurately located based on the permutation and combination of the location variable values ​​corresponding to the six bridge arms.

[0096] It should be noted that the working status of each bridge arm can be accurately determined by the six target averages. The permutation and combination of the six target averages can completely cover 22 cases, including no fault, single tube fault, and double tube fault. This can accurately determine the location of the fault, improve the efficiency of fault location, reduce the time for troubleshooting, and shorten the replacement and maintenance cycle.

[0097] Therefore, the solution provided in this application achieves the goal of determining the rate of change of the current vector angle based on the three-phase current signal of the inverter at different times, thereby determining whether the inverter has failed. This achieves the technical effect of improving fault detection efficiency and solves the technical problem of low detection efficiency caused by the complexity of the fault detection process of the inverter in the prior art.

[0098] Example 2

[0099] According to an embodiment of the present invention, an embodiment of an inverter fault detection device is provided, wherein, Figure 8 This is a schematic diagram of an optional inverter fault detection device according to an embodiment of the present invention, such as... Figure 8 As shown, the device includes:

[0100] The first determining module 801 is used to determine the period length of the acquisition period for acquiring the three-phase current signal output by the inverter, and to divide the time range corresponding to the period length into multiple first target time ranges.

[0101] The acquisition module 802 is used to acquire the three-phase current signal output by the inverter within the first target acquisition period to obtain a three-phase current signal group corresponding to each first target time range. Each three-phase current signal group consists of two three-phase current signals, and the acquisition times of the two three-phase current signals are the initial time and the end time of the first target time range, respectively.

[0102] The second determining module 803 is used to determine the first rate of change corresponding to each three-phase current signal group based on the three-phase current signals contained in each three-phase current signal group, wherein the first rate of change characterizes the rate of change of the current vector angle of the current three-phase current signal group within the first target time range.

[0103] The third determination module 804 is used to determine whether the inverter has malfunctioned based on the first rate of change corresponding to each three-phase current signal group.

[0104] It should be noted that the first determining module 801, the acquisition module 802, the second determining module 803 and the third determining module 804 mentioned above correspond to steps S101 to S104 in the above embodiments. The examples and application scenarios implemented by the four modules and the corresponding steps are the same, but are not limited to the content disclosed in the above embodiment 1.

[0105] Optionally, the second determining module further includes: a first transformation submodule, used to transform the first three-phase current signal from a three-phase stationary coordinate system to a two-phase stationary coordinate system to obtain a first current value of the first three-phase current signal on the α-axis and a second current value of the first three-phase current signal on the β-axis, wherein the first three-phase current signal and the second three-phase current signal are used to form a target three-phase current signal group, and the target three-phase current signal group is any one of multiple three-phase current signal groups; a second transformation submodule, used to transform the second three-phase current signal from a three-phase stationary coordinate system to a two-phase stationary coordinate system to obtain a third current value of the second three-phase current signal on the α-axis and a fourth current value of the second three-phase current signal on the β-axis; and a first determining submodule, used to determine a first rate of change corresponding to the target three-phase current signal group based on the first current value, the second current value, the third current value, the fourth current value, and a first target time range corresponding to the target three-phase current signal group.

[0106] Optionally, the third determining module further includes: a first calculation submodule, used to calculate the deviation between each first rate of change and the target rate of change to obtain multiple target deviation values, wherein the target rate of change is the rate of change of the current vector angle corresponding to the three-phase current signal when the inverter is not faulty; a second determining submodule, used to determine the average deviation value within the first target acquisition period based on each target deviation value and the first target time range corresponding to the target deviation value; and a third determining submodule, used to determine whether the inverter has failed based on the average deviation value and the target rate of change.

[0107] Optionally, the third determining submodule further includes: a calculation unit for calculating the ratio of the average deviation value to the target rate of change to obtain the calculation result; a first determining unit for determining that the inverter has failed if the calculation result is greater than or equal to a first preset threshold; and a second determining unit for determining that the inverter has not failed if the calculation result is less than the first preset threshold.

[0108] Optionally, the inverter fault detection device further includes: a fourth determining module, used to determine the target three-phase current signal of the inverter within the second target acquisition period if the inverter fails, wherein the period length of the first target acquisition period is the same as that of the second target acquisition period; and a decomposition module, used to decompose each phase current signal in the target three-phase current signal to obtain multiple current values ​​corresponding to each phase current signal within the second target time range, and multiple current values ​​corresponding to each phase current signal within the third target time range, wherein the time range corresponding to the second target acquisition period is composed of the second target time range and the third target time range. The processing module is used to normalize the current value of each phase current signal at the target time based on the target reference value corresponding to the target time, to obtain the first target per-unit quantity set corresponding to each phase current signal within the first target time range, and the second target per-unit quantity set corresponding to each phase current signal within the second target time range, wherein the target time is any time within the second target acquisition period, and the target reference value is a variable related to the time factor; the fifth determination module is used to determine the faulty insulated gate bipolar transistor from the insulated gate bipolar transistors in the inverter based on the first target per-unit quantity set and the second target per-unit quantity set.

[0109] Optionally, the inverter fault detection device further includes: a transformation module, used to transform the target three-phase current signal from a three-phase stationary coordinate system to a two-phase rotating coordinate system to obtain the current value information of the target three-phase current signal on the d-axis and the current value information of the target three-phase current signal on the q-axis; and a sixth determination module, used to determine the target reference value based on the current value information of the target three-phase current signal on the d-axis and the current value information of the target three-phase current signal on the q-axis.

[0110] Optionally, the fifth determining module further includes: a second calculation submodule, used to calculate the mean of the first target per-unit quantities contained in each first target per-unit quantity set to obtain a first target mean corresponding to each first target per-unit quantity set; a third calculation submodule, used to calculate the mean of the second target per-unit quantities contained in each second target per-unit quantity set to obtain a second target mean corresponding to each second target per-unit quantity set; a comparison module, used to compare each first target mean with a second preset threshold to obtain a first comparison result, and compare each second target mean with a second preset threshold to obtain a second comparison result; and a fourth determining submodule, used to determine the faulty insulated gate bipolar transistor in the inverter based on the first comparison result and the second comparison result.

[0111] Example 3

[0112] According to another aspect of the present invention, a computer-readable storage medium is also provided, wherein a computer program is stored in the computer-readable storage medium, and the computer program is configured to execute the above-described inverter fault detection method at runtime.

[0113] Example 4

[0114] According to another aspect of the present invention, an electronic device is also provided, wherein, Figure 9 This is a schematic diagram of an optional electronic device according to an embodiment of the present invention, such as... Figure 9 As shown, the electronic device includes one or more processors; and a memory for storing one or more programs, which, when executed by one or more processors, enable the one or more processors to run the programs, wherein the programs are configured to execute the inverter fault detection method described above during runtime.

[0115] The sequence numbers of the above embodiments of the present invention are for descriptive purposes only and do not represent the superiority or inferiority of the embodiments.

[0116] In the above embodiments of the present invention, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions of other embodiments.

[0117] In the several embodiments provided in this application, it should be understood that the disclosed technical content can be implemented in other ways. The device embodiments described above are merely illustrative; for example, the division of units can be a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the displayed or discussed mutual couplings, direct couplings, or communication connections may be through some interfaces; indirect couplings or communication connections between units or modules may be electrical or other forms.

[0118] The units described as separate components may or may not be physically separate. Similarly, the components shown as units may or may not be physical units; they may be located in one place or distributed across multiple units. Some or all of the units can be selected to achieve the purpose of this embodiment, depending on actual needs.

[0119] Furthermore, the functional units in the various embodiments of the present invention can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0120] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods of the various embodiments of the present invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, read-only memory (ROM), random access memory (RAM), portable hard drives, magnetic disks, or optical disks.

[0121] The above are merely preferred embodiments of the present invention. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A method for detecting inverter faults, characterized in that, include: The period length of the acquisition period for acquiring the three-phase current signal output by the inverter is determined, and the time range corresponding to the period length is divided into multiple first target time ranges. Within the first target acquisition period, the three-phase current signal output by the inverter is acquired to obtain a three-phase current signal group corresponding to each first target time range. Each three-phase current signal group consists of two three-phase current signals, and the acquisition times of the two three-phase current signals are the initial time and the end time of the first target time range, respectively. Based on the three-phase current signals contained in each three-phase current signal group, a first rate of change corresponding to each three-phase current signal group is determined, wherein the first rate of change characterizes the rate of change of the current vector angle of the current three-phase current signal group within the first target time range; Based on the first rate of change corresponding to each three-phase current signal group, determine whether the inverter has malfunctioned; If the inverter malfunctions, the target three-phase current signal corresponding to the inverter in the second target acquisition cycle is determined, wherein the first target acquisition cycle and the second target acquisition cycle have the same cycle length. The target three-phase current signal is decomposed to obtain multiple current values ​​corresponding to each phase current signal within a second target time range, and multiple current values ​​corresponding to each phase current signal within a third target time range. The time range corresponding to the second target acquisition period is composed of the second target time range and the third target time range. Based on the target reference value corresponding to the target time, the current value of each phase current signal corresponding to the target time is normalized to obtain the first target per-unit quantity set corresponding to each phase current signal within the first target time range, and the second target per-unit quantity set corresponding to each phase current signal within the second target time range. The target time is any time within the second target acquisition period, and the target reference value is a variable related to the time factor. Based on the first target per-unit set and the second target per-unit set, the faulty insulated gate bipolar transistor (IGBT) is determined from the insulated gate bipolar transistors in the inverter.

2. The method according to claim 1, characterized in that, Based on the three-phase current signals contained in each three-phase current signal group, determine the first rate of change corresponding to each three-phase current signal group, including: The first three-phase current signal is transformed from the three-phase stationary coordinate system to the two-phase stationary coordinate system to obtain the first three-phase current signal in... The first current value of the shaft, and the first three-phase current signal at The second current value of the shaft, wherein the first three-phase current signal and the second three-phase current signal are used to form a target three-phase current signal group, and the target three-phase current signal group is any one of a plurality of three-phase current signal groups; The second and third phase current signals are transformed from the three-phase stationary coordinate system to the two-phase stationary coordinate system to obtain the second and third phase current signals in... The third current value of the shaft, and the second three-phase current signal at The fourth current value of the shaft; Based on the first current value, the second current value, the third current value, the fourth current value, and the first target time range corresponding to the target three-phase current signal group, the first rate of change corresponding to the target three-phase current signal group is determined.

3. The method according to claim 1 or 2, characterized in that, Based on the first rate of change corresponding to each three-phase current signal group, determining whether the inverter has malfunctioned includes: Calculate the deviation between each first rate of change and the target rate of change to obtain multiple target deviation values, wherein the target rate of change is the rate of change of the current vector angle corresponding to the three-phase current signal when the inverter is not faulty; Based on each target deviation value and the first target time range corresponding to that target deviation value, the average deviation value within the first target acquisition period is determined; Based on the average deviation value and the target rate of change, it is determined whether the inverter has malfunctioned.

4. The method according to claim 3, characterized in that, Determining whether the inverter has malfunctioned based on the average deviation value and the target rate of change includes: Calculate the ratio of the average deviation value to the target rate of change to obtain the calculation result; If the calculation result is greater than or equal to the first preset threshold, then it is determined that the inverter has malfunctioned; If the calculation result is less than the first preset threshold, it is determined that the inverter has not malfunctioned.

5. The method according to claim 1, characterized in that, Before normalizing the current value of each phase current signal at the target time based on the target reference value at the target time, the method further includes: The target three-phase current signal is transformed from a three-phase stationary coordinate system to a two-phase rotating coordinate system to obtain the current value information of the target three-phase current signal on the d-axis and the current value information of the target three-phase current signal on the q-axis. The target reference value is determined based on the current value information of the target three-phase current signal on the d-axis and the current value information of the target three-phase current signal on the q-axis.

6. The method according to claim 1 or 5, characterized in that, Based on the first target per-unit value set and the second target per-unit value set, the faulty insulated-gate bipolar transistor (IGBT) is determined from the IGBTs in the inverter, including: The mean of the first target per-unit quantities contained in each first target per-unit quantity set is calculated to obtain the first target mean corresponding to each first target per-unit quantity set; The mean of the second target per-unit quantities contained in each set of second target per-unit quantities is calculated to obtain the mean of the second target corresponding to each set of second target per-unit quantities; Compare the mean of each first target with the second preset threshold to obtain a first comparison result, and compare the mean of each second target with the second preset threshold to obtain a second comparison result; Based on the first comparison result and the second comparison result, the faulty insulated gate bipolar transistor in the inverter is identified.

7. An inverter fault detection device, characterized in that, include: The first determining module is used to determine the period length of the acquisition period for acquiring the three-phase current signal output by the inverter, and to divide the time range corresponding to the period length into multiple first target time ranges. The acquisition module is used to acquire the three-phase current signal output by the inverter within the first target acquisition period to obtain a three-phase current signal group corresponding to each first target time range. Each three-phase current signal group consists of two three-phase current signals, and the acquisition times of the two three-phase current signals are the initial time and the end time of the first target time range, respectively. The second determining module is used to determine the first rate of change corresponding to each three-phase current signal group based on the three-phase current signals contained in each three-phase current signal group, wherein the first rate of change characterizes the rate of change of the current vector angle of the current three-phase current signal group within the first target time range; The third determining module is used to determine whether the inverter has malfunctioned based on the first rate of change corresponding to each three-phase current signal group. The fourth determining module is used to determine the target three-phase current signal of the inverter within the second target acquisition cycle if the inverter fails, wherein the first target acquisition cycle and the second target acquisition cycle have the same cycle length. The decomposition module is used to decompose each phase current signal in the target three-phase current signal to obtain multiple current values ​​corresponding to each phase current signal in the second target time range and multiple current values ​​corresponding to each phase current signal in the third target time range, wherein the time range corresponding to the second target acquisition cycle is composed of the second target time range and the third target time range; The processing module is used to normalize the current value of each phase current signal at the target time based on the target reference value corresponding to the target time, so as to obtain a first target per-unit quantity set corresponding to each phase current signal within a first target time range, and a second target per-unit quantity set corresponding to each phase current signal within a second target time range, wherein the target time is any time within the second target acquisition period, and the target reference value is a variable related to the time factor; The fifth determining module is used to determine the faulty insulated gate bipolar transistor (IGBT) from among the IGBTs in the inverter based on the first target per-unit set and the second target per-unit set.

8. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program, wherein the computer program is configured to execute the inverter fault detection method according to any one of claims 1 to 6 when it is run.

9. An electronic device, characterized in that, The electronic device includes one or more processors; A memory for storing one or more programs, which, when executed by one or more processors, cause the one or more processors to be configured to run the programs, wherein the programs are configured to execute the inverter fault detection method according to any one of claims 1 to 6.

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